LCD panel for a server system

ABSTRACT

A server system includes a plurality of printed circuit assemblies. The server system includes a chassis for housing the plurality of printed circuit assemblies. A server management card coupled to the plurality of printed circuit assemblies monitors and manages operation of the server system. The server management card receives and stores status information from the plurality of printed circuit assemblies. A first LCD panel is mounted on a first side of the chassis and is coupled to the server management card. A second LCD panel is mounted on a second side of the chassis and is coupled to the server management card.

THE FIELD OF THE INVENTION

The present invention relates to server systems. More particularly, theinvention relates to an LCD panel for a server system for providingconfiguration information and obtaining cPCI server status information.

BACKGROUND OF THE INVENTION

Console communications are used in server systems to send and receivestatus, control and configuration information. Console communicationsare typically transmitted and received via a single LAN interface (i.e.,a LAN that combines console and payload communications), or via a cableto an RS-232 port on a server.

When there is no console LAN, each server typically includes an RS-232port for console communications. If a large number of servers are to becontrolled, then a complex, hard-to-manage wiring bundle to eachindividual server's RS-232 port must be implemented. In addition, afull-featured CRT console is typically needed to connect to the RS-232port. Using an RS-232 port for console communications is sufficient fora standalone server, but when the server is integrated with many othersin a common chassis, a separate cable for each server is difficult tomaintain and configure. If any consolidation is to be done, it istypically implemented by a separate device outside of the chassis.Consequently, most customers route all of the cables a short distance toa special switch, such as those made by Raritan and Lantronics. Thoughthis simplifies the cable bundle by giving a single port of access tothe congregation of servers, it adds cost to the system in terms ofmoney and space. When the server is racked or put in a data center,floor space is at a premium and the use of a full-featured CRT isundesirable.

One vendor, Ziatech (www.ziatech.com), has provided a server system withan LCD panel for limited communications with the server system. However,the Ziatech LCD panel does not contain a lockout key for multi-userarbitration, nor does the panel include an alpha-numeric pad, and islimited in its functionality.

It would be desirable for a server system to eliminate the need forexternal devices for console communications, and provide an LCD panelfor local console communications that provides functionality beyond thatprovided by prior art systems.

SUMMARY OF THE INVENTION

One form of the present invention provides a server system including aplurality of printed circuit assemblies. The server system includes achassis for housing the plurality of printed circuit assemblies. Aserver management card coupled to the plurality of printed circuitassemblies monitors and manages operation of the server system. Theserver management card receives and stores status information from theplurality of printed circuit assemblies. A first LCD panel is mounted ona first side of the chassis and is coupled to the server managementcard. A second LCD panel is mounted on a second side of the chassis andis coupled to the server management card.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view illustrating a server systemaccording to one embodiment of the present invention.

FIG. 2 is a rear perspective view illustrating the server system shownin FIG. 1.

FIG. 3 is a block diagram illustrating major components of a serversystem according to one embodiment of the present invention.

FIG. 4 is a front view of one of LCD panels used by a server systemaccording to one embodiment of the present invention.

FIG. 5 is an electrical block diagram illustrating major components of aserver management card (SMC) according to one embodiment of the presentinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following detailed description of the preferred embodiments,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration specific embodiments inwhich the invention may be practiced. It is to be understood that otherembodiments may be utilized and structural or logical changes may bemade without departing from the scope of the present invention. Thefollowing detailed description, therefore, is not to be taken in alimiting sense, and the scope of the present invention is defined by theappended claims.

I. Server System

FIG. 1 is a front perspective view illustrating a server system 100according to one embodiment of the present invention. FIG. 2 is a rearperspective view illustrating server system 100. Server system 100includes panels 102, liquid crystal display (LCD) panels 104A and 104B(collectively referred to as LCD panels 104), backplane 106, chassis108, and dual redundant power supply units 114A and 114B (collectivelyreferred to as power supply units 114). Panels 102 are attached tochassis 108, and provide protection for the internal components ofserver system 100. Backplane 106 is positioned near the center of serversystem 100. Backplane 106 is also referred to as midplane 106. LCDpanels 104A and 104B are substantially identical, except for theirplacement on server system 100. LCD panel 104A is positioned on a frontside of server system 100, and LCD panel 104B is positioned on a backside of server system 100.

Power supply units 114 are positioned at the bottom of server system 100and extend from a back side of server system 100 to a front side ofserver system 100. Power supply units 114 each include an associatedcooling fan 304 (shown in block form in FIG. 3). In one form of theinvention, additional cooling fans 304 are positioned behind LCD panel104B. In one embodiment, 4 chassis cooling fans 304 are used in serversystem 100. In an alternative embodiment, 6 chassis cooling fans 304 areused. Other numbers and placement of cooling fans 304 may be used. Inone form of the invention, cooling fans 304 form an N+1 redundantcooling system, where “N” represents the total number of necessary fans304, and “1” represents the number of redundant fans 304.

In one embodiment, server system 100 supports the Compact PeripheralComponent Interconnect (cPCI) form factor of printed circuit assemblies(PCAs). Server system 100 includes a plurality of cPCI slots 110 forreceiving cards/modules 300 (shown in block form in FIG. 3). In oneembodiment, system 100 includes ten slots 110 on each side of backplane106 (referred to as the 10 slot configuration). In an alternativeembodiment, system 100 includes nineteen slots 110 on each side ofbackplane 106 (referred to as the 19 slot configuration). Additionalalternative embodiments use other slot configurations.

FIG. 3 is a block diagram illustrating major components of server system100. Server system 100 includes backplane 106, a plurality ofcards/modules 300A-300G (collectively referred to as cards 300), fans304, electrically erasable programmable read only memory (EEPROM) 314,LEDs 322, LCD panels 104, power supply units (PSUs) 114, and temperaturesensor 324. Cards 300 are inserted in slots 110 (shown in FIGS. 1 and 2)in system 100. In one form of the invention, cards 300 may occupy morethan one slot 110. In one embodiment, cards 300 include host processorcards 300A, hard disk cards 300B, managed Ethernet switch cards 300C and300D, a server management card (SMC) 300E, and 2 redundant SMC localarea network (LAN) rear transition modules (RTMs) 300F and 300G. In oneembodiment, there is one managed Ethernet switch card 300C fitted in the10 slot chassis embodiment, and up to two managed Ethernet switch cards300C and 300D fitted in the 19 slot chassis embodiment. In one form ofthe invention, managed Ethernet switch cards 300C and 300D are“Procurve” managed Ethernet switch cards.

In one embodiment, two types of host processor cards 300A may be used inserver system 100—PA-RISC host processor cards and IA32 host processorcards. Multiple host processor cards 300A and hard disk cards 300B areused in embodiments of server system 100, but are each represented by asingle card in FIG. 3 to simplify the figure. In one form of theinvention, up to 8 host processor cards 300A are used in the 10 slotconfiguration, and up to 16 host processor cards 300A are used in the 19slot configuration. In one embodiment, each of cards 300 can be hotswapped.

In one embodiment, cards 300 each include a pair of EEPROMs 302A and302B, which are discussed below. Power supply units 114 each include anEEPROM 323 for storing power supply identification and statusinformation. Fans 304 include associated sensors 306 for monitoring thespeed of the fans 304. In one embodiment, LEDs 322 include eight statusLEDs, six LAN LEDs to indicate the speed and link status of LAN links318, a blue hot swap SMC 300E, a power-on indicator LED, and three fancontrol indicator LEDs.

The operational health of cards 300 and system 100 are monitored by SMC300E to ensure the reliable operation of the system 100. SMC 300Eincludes serial ports 310 (discussed below), and an extraction lever 308with an associated switch. In one embodiment, all cards 300 include anextraction lever 308 with an associated switch.

In one embodiment, SMC 300E is the size of a typical compact PCI (cPCI)card, and supports PA-RISC and the IA32 host processor cards 300A. SMC300E electrically connects to other components in system 100, includingcards 300, temperature sensor 324, power supply units 114, fans 304,EEPROM 314, LCD panels 104, LEDs 322, and SMC rear transition modules300F and 300G via backplane 106. In most cases, the connections are viaI²C buses 554 (shown in FIG. 5), as described in further detail below.The I²C buses 554 allow bidirectional communication so that statusinformation can be sent to SMC 300E and configuration information sentfrom SMC 300E. In one embodiment, SMC 300E uses I²C buses 554 to obtainenvironmental information from power supply units 114, host processorcards 300A, and other cards 300 fitted into system 100.

SMC 300E also includes a LAN switch 532 (shown in FIG. 5) to connectconsole management LAN signals from the host processor cards 300A to anexternal management network (also referred to as management LAN) 320 viaone of the two SMC rear transition modules 300F and 300G. In oneembodiment, the two SMC rear transition modules 300F and 300G eachprovide external 10/100Base-T LAN links 318 for connectivity tomanagement LAN 320. In one embodiment, SMC rear transition modules 300Fand 300G are fibre-channel, port-bypass cards

Managed Ethernet switch cards 300C and 300D are connected to hostprocessor cards 300A through backplane 106, and include external10/100/1000Base-T LAN links 301 for connecting host processor cards toexternal customer or payload LANs 303. Managed Ethernet switch cards300C and 300D are fully managed LAN switches.

II. LCD Panel

FIG. 4 is a front view of one of LCD panels 104. In one form of theinvention, each LCD panel 104 includes a 2×20 LCD display 400, 10alphanumeric keys 402, 5 menu navigation/activation keys 404A-404E(collectively referred to as navigation keys 404), and a lockout key 406with associated LED (not shown) that lights lockout key 406. If a userpresses a key 402, 404, or 406, an alert signal is generated and SMC300E polls the LCD panels 104A and 104B to determine which LCD panel wasused, and the key that was pressed.

Alphanumeric keys 402 allow a user to enter alphanumeric strings thatare sent to SMC 300E. Navigation keys 404 allow a user to navigatethrough menus displayed on LCD display 400, and select desired menuitems. Navigation keys 404A and 404B are used to move left and right,respectively, within the alphanumeric strings. Navigation key 404C is an“OK/Enter” key. Navigation key 404D is used to move down. Navigation key404E is a “Cancel” key.

LCD panels 104 provide access to a test shell (discussed below) thatprovides system information and allows configuration of system 100. Asdiscussed below, other methods of access to the test shell are alsoprovided by system 100. To avoid contention problems between the two LCDpanels 104, and the other methods of access to the test shell, a lockoutkey 406 is provided on LCD panels 104. A user can press lockout key 406to gain or release control of the test shell. In one embodiment, lockoutkey 406 includes an associated LED to light lockout key 406 and indicatea current lockout status.

In one embodiment, the LED associated with lockout key 406 indicates alockout status as follows: (1) LED Off: quiescent state, with no lockoutin place, no access to test shell; (2) Green: lockout in place and thisLCD panel 104 is the controlling connection; and (3) Flashing green:lockout in place and this LCD panel 104 is not the controllingconnection. If the lockout LED is off or flashing then pressing thelockout key 406 gains control of the test shell. The lockout LED willthen go on. If the lockout LED is on, pressing the lockout key 406releases control of the test shell. The LED then goes off.

In one embodiment, LCD panels 104 also provide additional information tothat displayed by LEDs 322 during start-up. If errors are encounteredduring the start-up sequence, LCD panels 104 provide more informationabout the error without the operator having to attach a terminal to oneof the SMC serial ports 310.

Having the LCD panels 104 integrated into server system 100, as opposedto requiring a separate I/O connection through the bulkhead of eachserver module as in prior art systems, provides a consistent, lesscostly, space saving, and visually attractive solution for local controlof server system 100. In addition, the lockout key 406 of LCD panels 104prevents users from corrupting data settings due to simultaneous accessof the configuration space. In one embodiment, with a completealpha-numeric keypad 402, every aspect of SMC 300E can be programmedfrom the local LCD panels 104.

III. Server Management Card (SMC)

A. SMC Overview

FIG. 5 is an electrical block diagram illustrating major components ofserver management card (SMC) 300E. SMC 300E includes flash memory 500,processor 502, dynamic random access memory (DRAM) 504, PCI bridge 506,field programmable gate array (FPGA) 508, output registers 510A and510B, input registers 512A and 512B, fan controllers 526A-526C(collectively referred to as fan controllers 526), network controller530, LAN switch 532, universal asynchronous receiver transmitter (UART)with modem 534, dual UART 536, UART with modem 538, clockgenerator/watchdog 540, battery 542, real time clock (RTC) 544,non-volatile random access memory (NVRAM) 546, I²C controllers 548A-548H(collectively referred to as I²C controllers 548), EEPROM 550, andtemperature sensor 324. In one embodiment, components of SMC 300E areconnected together via PCI buses 507. In one form of the invention, PCIbuses 507 are not routed between slots 110. Switched LAN signals throughLAN switch 532 are routed between slots 110.

Functions of SMC 300E include supervising the operation of othercomponents within system 100 (e.g. fan speed, temperature, card present)and reporting their health to a central location (e.g., externalmanagement network 320), reporting any failures to a central location(e.g., external management network 320), providing a LAN switch 532 toconnect console management LAN signals from the SMC 300E and hostprocessor cards 300A to an external management network 320, andproviding an initial boot configuration for the system 100.

B. SMC Processor and Memory

SMC 300E includes chassis management processor 502. In one embodiment,chassis management processor 502, also referred to as SMC processor 502,is a StrongARM SA-110 processor with supporting buffer. In oneembodiment, SMC 300E uses a Linux operating system. SMC 300E also runsserver management application (SMA) software/firmware. In oneembodiment, the operating system and SMA are stored in flash memory 500.In one form of the invention, all information needed to power-up SMC300E, and for SMC 300E to become operational, are stored in flash memory500. In one embodiment, flash memory 500 includes 4 to 16 Mbytes ofstorage space to allow SMC 300E to boot-up as a stand-alone card (i.e.,no network connection needed).

SMC 300E also includes DRAM 504. In one embodiment, DRAM 504 includes32, 64 or 128 Mbytes of storage space. In one form of the invention, ahardware fitted table is stored in DRAM 504. The hardware fitted tableincludes information representing the physical configuration of system100. The hardware fitted table changes if there is a physical change tosystem 100, such as by a hardware device being added to or removed fromsystem 100. The hardware fitted table includes hardware type information(e.g., whether a device is an IA32/PA-RISC/Disk Carrier/RTM (i.e., reartransition module)/PSU/LCD panel/Modem/Unknown device, etc.), hardwarerevision and serial number, status information, configurationinformation, and hot-swap status information.

Processor 502 is coupled to FPGA 508. FPGA 508 includes 6 sets ofinput/output lines 522A-522F. Lines 522A are connected to jumpers forconfiguring SMC 300E. Lines 522B are hot swap lines for monitoring thehot swap status of cards 300. In one embodiment, hot swap lines 522Binclude 18 hot swap status input lines, which allow SMC 300E todetermine the hot swap status of the host processor cards 300A, harddisk cards 300B, managed Ethernet switch cards 300C and 300D, SMC reartransition modules 300F and 300G, and power supply units 114. Lines 522Care LED lines that are coupled to LEDs 322. Lines 522D are fan inputlines that are coupled to fan sensors 306 for monitoring the speed offans 304. Lines 522E are power supply status lines that are coupled topower supply units 114 for determining whether both, or only one powersupply unit 114 is present. Lines 522F are SMB alert lines forcommunicating alert signals related to SMB I²C buses 554B, 554D, and554F.

C. Clock, Battery & NVRAM

SMC 300E includes a real time clock (RTC) 544 and an associated battery542 to preserve the clock. Real time clock 544 provides the correct timeof day. SMC 300E also includes NVRAM 546 for storing clock information.In one embodiment, NVRAM 546 uses the same battery as real time clock544.

D. LAN Switch

SMC 300E sends and receives management LAN communications through PCIbridge 506 and controller 530 to LAN switch 532. In one embodiment, LANswitch 532 is an unmanaged LAN switch including 19 ports, with two portsconnected to SMC rear transition modules 300F and 300G (shown in FIG. 3)via links 531A for communications with external management network 320(shown in FIG. 3), 16 ports for connecting to the management LANconnections of up to 16 host processor cards 300A via links 531B throughbackplane 106, and one port for connecting to the SMC's LAN port (i.e.,output of controller 530) via links 531C. SMC 300E provides managementsupport for console LAN management signals sent and received through LANswitch 532. SMC 300E provides control of management LAN signals of hostprocessor cards 300A, managed Ethernet switches 300C and 300D, SMCprocessor 502, and SMC rear transition modules 300F and 300G. SMC 300Emonitors the status of the management LAN connections of up to 16 hostprocessor cards 300A to LAN switch 532, and reports an alarm event ifany of the connections are lost. FPGA 508 and LAN switch 532 are coupledtogether via an RS-232 link 533 for the exchange of control and statusinformation.

E. I²C Buses

Server system 100 includes eight I²C buses 554A-554H (collectivelyreferred to as I²C buses 554) to allow communication with componentswithin system 100. I²C buses 554 are coupled to FPGA 508 via I²Ccontrollers 548. In one embodiment, the I²C buses 554 include 3intelligent platform management bus (IPMB) buses 554A, 554C, and 554E, 3system management bus (SMB) buses 554B, 554D, and 554F, a backplane IDbus (BP) 554G, and an I²C bus 554H for accessing SMC EEPROM 550 andchassis temperature sensor 324. A different number and configuration ofI²C buses 554 may be used depending upon the desired implementation. SMC300E maintains a system event log (SEL) within non-volatile flash memory500 for storing information gathered over I²C buses 554.

The IPMB I²C buses 554A, 554C, and 554E implement the intelligentplatform management interface (IPMI) specification. The IPMIspecification is a standard defining an abstracted interface to platformmanagement hardware. IPMI is layered over the standard I²C protocol. SMC300E uses one or more of the IPMB I²C buses 554A, 554C, and 554E toretrieve static data from each of the host processor cards 300A and harddisk cards 300B. The static data includes identification information foridentifying each of the cards 300A and 300B. Each slot 110 in system 100can be individually addressed to retrieve the static configuration datafor the card 300 in that slot 110. In one embodiment, the host processorcards 300A and hard disk cards 300B each include an EEPROM 302A (shownin FIG. 3) that stores the static identification information retrievedover IPMB I²C buses 554A, 554C, and 554E. In one embodiment, each EEPROM302A contains the type of card, the name of the card, the hardwarerevision of the card, the card's serial number and card manufacturinginformation.

SMC 300E also uses one or more of the IPMB I²C buses 554A, 554C, and554E, to retrieve dynamic environmental information from each of thehost processor cards 300A and hard disk cards 300B. In one embodiment,this dynamic information is held in a second EEPROM 302B (shown in FIG.3) on each of the cards 300A and 300B. In one form of the invention, thedynamic board data includes card temperature and voltage measurements.In one embodiment, SMC 300E can write information to the EEPROMs 302Aand 302B on cards 300.

The three SMB I²C buses 554B, 554D, and 554F also implement the IPMIspecification. The three SMB I²C buses 554B, 554D, and 554F, are coupledto LEDs 322, the two LCD panels 104, the dual redundant power supplyunits 114, and some of the host processor cards 300A. SMC 300E uses oneor more of the SMB I²C buses 554B, 554D, and 554F, to provide consolecommunications via the LCD panels 104. In order for the keypadkey-presses on the LCD panels 104 to be communicated back to SMC 300E,an alert signal is provided when keys are pressed that causes SMC 300Eto query LCD panels 104 for the keys that were pressed.

SMC 300E communicates with power supply units 114 via one or more of theSMB I²C buses 554B, 554D, and 554F to obtain configuration and statusinformation including the operational state of the power supply units114. In one embodiment, the dual redundant power supply units 114provide voltage rail measurements to SMC 300E. A minimum and maximumvoltage value is stored by the power supply units 114 for each measuredrail. The voltage values are polled by SMC 300E at a time intervaldefined by the current configuration information for SMC 300E. If avoltage measurement goes out of specification, defined by maximum andminimum voltage configuration parameters, SMC 300E generates an alarmevent. In one embodiment, power supply units 114 store configuration andstatus information in their associated EEPROMs 323 (shown in FIG. 3).

Backplane ID Bus (BP) 554G is coupled to backplane EEPROM 314 (shown inFIG. 3) on backplane 106. SMC 300E communicates with the backplaneEEPROM 314 over the BP bus 554G to obtain backplane manufacturing data,including hardware identification and revision number. On start-up, SMC300E communicates with EEPROM 314 to obtain the manufacturing data,which is then added to the hardware fitted table. The manufacturing dataallows SMC 300E to determine if it is in the correct chassis for theconfiguration it has on board, since it is possible that the SMC 300Ehas been taken from a different chassis and either hot-swapped into anew chassis, or added to a new chassis and the chassis is then poweredup. If there is no valid configuration on board, or SMC 300E cannotdetermine which chassis it is in, then SMC 300E waits for a pushedconfiguration from external management network 320, or for a manual userconfiguration via one of the connection methods discussed below.

In one embodiment, there is a single temperature sensor 324 withinsystem 100. SMC 300E receives temperature information from temperaturesensor 324 over I²C bus 554H. SMC 300E monitors and records thistemperature and adjusts the speed of the cooling fans 304 accordingly,as described below. SMC also uses I²C bus 554H to access EEPROM 550,which stores board revision and manufacture data for SMC 300E.

F. Serial Ports

SMC 300E includes 4 RS-232 interfaces 310A-310D (collectively referredto as serial ports 310). RS-232 serial interface 310A is via a 9-pinMale D-type connector on the front panel of SMC 300E. The other threeserial ports 310B-310D are routed through backplane 106. The front panelRS-232 serial interface 310A is connected via a UART with a full modem534 to FPGA 508, to allow monitor and debug information to be madeavailable via the front panel of SMC 300E. Backplane serial port 310D isalso connected via a UART with a full modem 538 to FPGA 508. In oneembodiment, backplane serial port 310D is intended as a debug or consoleport. The other two backplane serial interfaces 310B and 310C areconnected via a dual UART 536 to FPGA 508, and are routed to managedEthernet switches 300C and 300D through backplane 106. These twobackplane serial interfaces 310B and 310C are used to connect to andconfigure the managed Ethernet switch cards 300C and 300D, and to obtainstatus information from the managed Ethernet switch cards 300C and 300D.

G. Fans and Temperature Control

In one embodiment, server system 100 includes six chassis fans 304.Server system 100 includes temperature sensor 324 to monitor the chassistemperature, and fan sensors 306 to monitor the six fans 304. In oneembodiment, fan sensors 306 indicate whether a fan 304 is rotating andthe fan's speed setting. In one form of the invention, FPGA 508 includes6 fan input lines 522D (i.e., one fan input line 522D from each fansensor 306) to monitor the rotation of the six fans 304, and a singlefan output line 524 coupled to fan controllers 526A-526C. Fancontrollers 526A-526C control the speed of fans 304 by a PWM (pulsewidth modulation) signal via output lines 528A-528F. If a fan 304stalls, the monitor line 522D of that fan 304 indicates this conditionto FPGA 508, and an alarm event is generated. The speed of fans 304 isvaried to maintain an optimum operating temperature versus fan noisewithin system 100. If the chassis temperature sensed by temperaturesensor 324 reaches or exceeds a temperature alarm threshold, an alarmevent is generated. When the temperature reduces below the alarmthreshold, the alarm event is cleared. If the temperature reaches orexceeds a temperature critical threshold, the physical integrity of thecomponents within system 100 are considered to be at risk, and SMC 300Eperforms a system shut-down, and all cards 300 are powered down exceptSMC 300E. When the chassis temperature falls below the criticalthreshold and has reached the alarm threshold, SMC 300E restores thepower to all of the cards 300 that were powered down when the criticalthreshold was reached.

In one embodiment, SMC 300E controls the power state of cards 300 usingpower reset (PRST) lines 514 and power off (PWR_OFF) lines 516. FPGA 508is coupled to power reset lines 514 and power off lines 516 via outputregisters 510A and 510B, respectively. In one embodiment, power resetlines 514 and power off lines 516 each include 19 output lines that arecoupled to cards 300. SMC 300E uses power off lines 516 to turn off thepower to selected cards 300, and uses power reset lines 514 to resetselected cards 300. In one embodiment, a lesser number of power resetand power off lines are used for the 10 slot chassis configuration.

H. Clock Generator/Watchdog

SMC 300E is protected by both software and hardware watchdog timers. Thewatchdog timers are part of clock generator/watchdog block 540, whichalso provides a clock signal for SMC 300E. The hardware watchdog timeris started before software loading commences to protect against failure.In one embodiment, the time interval is set long enough to allow aworst-case load to complete. If the hardware watchdog timer expires, SMCprocessor 502 is reset.

I. Modes of Operation

In one embodiment, SMC 300E has three phases or modes ofoperation—Start-up, normal operation, and hot swap. The start-up mode isentered on power-up or reset, and controls the sequence needed to makeSMC 300E operational. SMC 300E also provides minimal configurationinformation to allow chassis components to communicate on the managementLAN. The progress of the start-up procedure can be followed on LEDs 322,which also indicate any errors during start-up.

The normal operation mode is entered after the start-up mode hascompleted. In the normal operation mode, SMC 300E monitors the health ofsystem 100 and its components, and reports alarm events. SMC 300Emonitors the chassis environment, including temperature, fans, inputsignals, and the operational state of the host processor cards 300A.

SMC 300E reports alarm events to a central point, namely an alarm eventmanager, via the management LAN (i.e., through LAN switch 532 and one ofthe two SMC rear transition modules 300F or 300G to external managementnetwork 320). The alarm event manager is an external module that is partof external management network 320, and that handles the alarm eventsgenerated by server system 100. The alarm event manager decides what todo with received alarms and events, and initiates any recovery orreconfiguration that may be needed. In addition to sending the alarmevents across the management network, a system event log (SEL) ismaintained in SMC 300E to keep a record of the alarms and events. TheSEL is held in non-volatile flash memory 500 in SMC 300E and ismaintained over power cycles, and resets of SMC 300E.

In the normal operation mode, SMC 300E may receive and initiateconfiguration commands and take action on received commands. Theconfiguration commands allow the firmware of SMC processor 502 and thehardware controlled by processor 502 to be configured. This allows theoperation of SMC 300E to be customized to the current environment.Configuration commands may originate from the management network 320,one of the local serial ports 310 via a test shell (discussed below), orone of the LCD panels 104.

The hot swap mode is entered when there is an attempt to remove a card300 from system 100. In one embodiment, all of the chassis cards 300 canbe hot swapped, including SMC 300E, and the two power supply units 114.An application shutdown sequence is initiated if a card 300 is to beremoved. The shutdown sequence performs all of the steps needed to readythe card 300 for removal.

In one embodiment, FPGA 508 includes 18 hot swap status inputs 522B.These inputs 522B allow SMC 300E to determine the hot swap status ofhost processor cards 300A, hard disk cards 300B, managed Ethernet switchcards 300C and 300D, SMC rear transition module cards 300F and 300G, andpower supply units 114. The hot-swap status of the SMC card 300E itselfis also determined through this interface 522B.

An interrupt is generated and passed to SMC processor 502 if any of thecards 300 in system 100 are being removed or installed. SMC 300Emonitors board select (BD_SEL) lines 518 and board healthy (HEALTHY)lines 520 of cards 300 in system 100. In one embodiment, board selectlines 518 and healthy lines 520 each include 19 input lines, which areconnected to FPGA 508 via input registers 512A and 512B, respectively.SMC 300E monitors the board select lines 518 to sense when a card 300 isinstalled. SMC 300E monitors the healthy lines 520 to determine whethercards 300 are healthy and capable of being brought out of a reset state.

When SMC 300E detects that a card has been inserted or removed, an alarmevent is generated. When a new card 300 is inserted in system 100, SMC300E determines the type of card 300 that was inserted by polling theidentification EEPROM 302A of the card 300. Information is retrievedfrom the EEPROM 302A and added to the hardware fitted table. SMC 300Ealso configures the new card 300 if it has not been configured, or ifits configuration differs from the expected configuration. When a card300, other than the SMC 300E, is hot-swapped out of system 100, SMC 300Eupdates the hardware fitted table accordingly.

In one embodiment, SMC 300E is extracted in three stages: (1) aninterrupt is generated and passed to the SMC processor 502 when theextraction lever 308 on the SMC front panel is set to the “extraction”position in accordance with the Compact PCI specification, indicatingthat SMC 300E is about to be removed; (2) SMC processor 502 warns theexternal management network 320 of the SMC 300E removal and makes theextraction safe; and (3) SMC processor 502 indicates that SMC may beremoved via the blue hot swap LED 322. SMC 300E ensures that anyapplication download and flashing operations are complete before the hotswap LED 322 indicates that the card 300E may be removed.

J. User Connectivity

In one embodiment, there are two test shells implemented within SMC300E. There is an application level test shell that is a normal,run-time, test shell accessed and used by users and applications. Thereis also a stand-alone test shell that is a manufacturer test shellresiding in flash memory 500 that provides manufacturing leveldiagnostics and functions. The stand-alone test shell is activated whenSMC 300E boots and an appropriate jumper is in place on SMC 300E. Thestand-alone test shell allows access to commands that the user wouldnot, or should not have access to.

The test shells provide an operator interface to SMC 300E. This allowsan operator to query the status of system 100 and (with the requiredauthority level) to change the configuration of system 100.

A user can interact with the test shells by a number of differentmethods, including locally via a terminal directly attached to one ofthe serial ports 310, locally via a terminal attached by a modem to oneof the serial ports 310, locally via one of the two LCD panels 104, andremotely via a telnet session established through the management LAN320. A user may connect to the test shells by connecting a terminal toeither the front panel serial port 310A or rear panel serial ports310B-310D of SMC 300E, depending on the console/modem serial portconfiguration. The RS-232 and LAN connections provide a telnet consoleinterface. LCD panels 104 provide the same command features as thetelnet console interface. SMC 300E can function as either a dial-infacility, where a user may establish a link by calling to the modem, oras a dial-out facility, where SMC 300E can dial out to a configurednumber.

The test shells provide direct access to alarm and event statusinformation. In addition, the test shells provides the user with accessto other information, including temperature logs, voltage logs, chassiscard fitted table, and the current setting of all the configurationparameters. The configuration of SMC 300E may be changed via the testshells. Any change in configuration is communicated to the relevantcards 300 in system 100. In one embodiment, configuration informationdownloaded via a test shell includes a list of the cards 300 expected tobe present in system 100, and configuration data for these cards 300.The configuration information is stored in flash memory 500, and is usedevery time SMC 300E is powered up.

K. Multiple Connections

SMC 300E allows more than one active connection to the test shell at atime and arbitrates control between multiple users. For example, if anRS-232 connection is being used and a telnet connection through themanagement LAN 320 is started up, both connections are managed by SMC300E. Similarly, multiple telnet connections via the management LAN 320can be established at any one time. If more than one user is logged onto SMC 300E, then a single user has “master” control over the test shelland the displays “mirror” each other. That is, the input and output onthe master user's display is reflected on the display of all otherusers, with the exception of LCD panels 104. By mirroring the activityof one console session to another, the owner of server system 100 canreceive instructions or monitor the activity from field supportpersonnel. Command input is disabled for all users except the masteruser. A user of an LCD panel 104 has the ability to obtain mastercontrol over the test shell through use of the lockout button 406. Auser logged in to the test shell through a LAN telnet session or by anRS-232 connection has the ability to obtain master control over the testshell if the access level of that user is the same as or higher than thecurrent master user.

In one embodiment, a secure shell (SSH) client is used for LAN and modemconnections to SMC 300E. Any device wishing to make a connection to SMC300E must make this connection through a secure shell client. In oneform of the invention, access to SMC 300E via the LCD panels 104 is notprotected by a secure shell.

Three levels of access to the test shells are provided: user(read-only), configuration-user (user+configuration access), andsuper-user (configuration+password protection access). A user at ahigher level can force a user at a lower level to be logged out forsecurity reasons. Some test shell commands are only available to usersat configuration-user or super-user levels. If an attempt is made toexecute a command for which the user does not have the required accesslevel, an appropriate error message is displayed and the command isignored. A user with super-user level access is provided the ability tochange passwords. In one embodiment, LCD panels 104 provideconfiguration-user level access.

With multiple methods of accessing the test shell, SMC 300E allows forsimultaneous access to one or more cards 300 within server system 100.The multiple methods of accessing the test shell are transparentlymapped to multiple types of connections to the various cards 300 withinserver system 100. As described above, SMC 300E gathers information fromcards 300 via a variety of connections with a variety of protocols,including serial communications through RS-232 link 533, IPMIcommunications over I²C buses 554, and LAN communications throughhub/switch 532. The multiple methods of accessing the test shell arerouted into processor 502, which buffers the input protocol required bythe various cards 300. All of the underlying connection and protocoldetails are hidden from the user, who can work through a singleinterface to access card information.

Although specific embodiments have been illustrated and described hereinfor purposes of description of the preferred embodiment, it will beappreciated by those of ordinary skill in the art that a wide variety ofalternate and/or equivalent implementations may be substituted for thespecific embodiments shown and described without departing from thescope of the present invention. Those with skill in the chemical,mechanical, electro-mechanical, electrical, and computer arts willreadily appreciate that the present invention may be implemented in avery wide variety of embodiments. This application is intended to coverany adaptations or variations of the preferred embodiments discussedherein. Therefore, it is manifestly intended that this invention belimited only by the claims and the equivalents thereof.

What is claimed is:
 1. A server system comprising: a plurality ofprinted circuit assemblies; a server management card coupled to theplurality of printed circuit assemblies for monitoring and managingoperation of the server system, the server management card receiving andstoring status information from the plurality of printed circuitassemblies; a first LCD panel mounted on a front panel of the serversystem and coupled to the server management card, the first LCD panelproviding a user interface for configuring the server management cardand accessing the stored status information from the server managementcard, the first LCD panel including a user selectable lockout mechanismfor controlling access to the server management card; and a second LCDpanel substantially similar to the first LCD panel mounted on a backpanel of the server system.
 2. The server system of claim 1, wherein thefirst LCD panel includes an LCD display, and a plurality of alphanumerickeys for entering alphanumeric information.
 3. The server system ofclaim 2, wherein the first LCD panel further includes a plurality ofnavigation keys for navigating through menus displayed on the LCDdisplay.
 4. The server system of claim 1, wherein the server managementcard includes a set of user interfaces in addition to the first LCDpanel for configuring the server management card and accessing thestored status information from the server management card.
 5. The serversystem of claim 4, wherein the set of user interfaces to the servermanagement card includes at least one of a second LCD panel, a serialinterface, and a LAN interface.
 6. The server system of claim 4, whereinthe lockout mechanism comprises a lockout key for arbitrating control ofthe server management card between the first LCD panel and the set ofuser interfaces.
 7. The server system of claim 6, wherein the first LCDpanel includes an LED associated with the lockout key for indicating alockout status.
 8. A method of communicating with a computer system toconfigure the computer system and obtain status information from cardsfitted in the computer system, the method comprising: providing amanagement card in the computer system; transmitting status informationfrom the cards fitted in the computer system to the management card;providing first and second LCD panels mounted on the computer system andcoupled to the management card; transmitting the status information fromthe management card to the first and the second LCD panels; anddisplaying the received status information on an LCD display of thefirst LCD panel and on an LCD display of the second LCD panel.
 9. Themethod of claim 8, and further comprising: providing a set of userinterfaces to the management card including at least one serial portinterface and at least one LAN interface.
 10. The method of claim 9, andfurther comprising: providing a lockout key on the first LCD panel forgaining control of the management card and locking out control of themanagement card through one of the interfaces in the set of userinterfaces.
 11. The method of claim 10, and further comprising:providing a lockout status indication on the first LCD panel to indicatea lockout status.
 12. The method of claim 10, and further comprising:providing a lockout key on the second LCD panel for gaining control ofthe management card and locking out control of the management cardthrough one of the interfaces in the set of user interfaces.
 13. Themethod of claim 12, and further comprising: providing a lockout statusindication on the second LCD panel to indicate a lockout status.
 14. Themethod of claim 8, and further comprising: navigating through a menudisplayed on the LCD display of the first LCD panel using navigationkeys on the first LCD panel.
 15. The method of claim 8, and furthercomprising: entering configuration information on a keypad of the firstLCD panel; transmitting the configuration information from the first LCDpanel to the management card; and storing the configuration informationon the management card.
 16. A server system comprising: a plurality ofprinted circuit assemblies; a chassis for housing the plurality ofprinted circuit assemblies; a server management card coupled to theplurality of printed circuit assemblies for monitoring and managingoperation of the server system, the server management card receiving andstoring status information from the plurality of printed circuitassemblies; a first LCD panel mounted on a first side of the chassis andcoupled to the server management card; and a second LCD panel mounted ona second side of the chassis and coupled to the server management card.17. The server system of claim 16, wherein the first and the second LCDpanels each provide a user interface for configuring the servermanagement card and accessing the stored status information from theserver management card.
 18. The server system of claim 16, wherein atleast one of the first and the second LCD panels includes a userselectable lockout mechanism for gaining and releasing control of theserver management card.